Väisälä is a tiny lunar crater located on a rise in the Oceanus Procellarum. Sharing the same continental island are the larger Aristarchus crater to the south-southeast and Herodotus crater to the south-southwest. Väisälä lies just to the west of the Rupes Toscanelli fault line, and the Rimae Aristarchus rille system. To the southwest is the notable Vallis Schröteri cleft.

This formation is circular and cup-shaped, with a higher albedo than the surrounding dark surface. It was previously designated 'Aristarchus A' before being given its current name by the IAU.